Stability of preference for odors after short-term exposure in young spiny mice

The stability of olfactory preferences for artificial odors was studied in young spiny mouse pups (Acomys cahirinus). Subjects aged between 2 and 20 days were exposed to the odor of either cinnamon or cumin for 1.5 hr. The durability of preferences for the familiar versus novel odor was subsequently monitored in a three-choice preference test. The results suggest the existence of a sensitive phase for learning odor characteristics, through simple exposure, between Days 2 and 18 of the pups' postnatal life. The sensitive phase proved not to be an "on-off" process, but the strongest effect of exposure to odors took place at about Days 4 and 6. However, the duration of preference for exposed odors was dependent on later experience with the odors during retests. The results point to an unusual plasticity in rapid learning of odors through simple exposure in precocial young spiny mice.